Engineered to improve engine cleanliness and performance, ACDelco dexos1 Synthetic Motor Oils are composed of high-quality synthetic base stocks and exceptional additive technology. ACDelco dexos1 Synthetic Motor Oil is the General Motors factory fill and the required service fill for GM vehicles with gasoline engines beginning with the 2011 model year. Recommended for use in cars and light trucks with gasoline and gasoline turbocharged engines where API SN and all prior specifications are required.